/Engine/Source/Runtime/GeometryCore/Public/Spatial/GeometrySet3.h
PointWithinToleranceTest is called in parallel and hence must be thread-safe/re-entrant!
true if the nearest point on Ray to some point in the set passed the PointWithinToleranceTest.
bool FindNearestPointToRay ( const FRay3d & Ray, [FNearest](API\Runtime\GeometryCore\Spatial\FGeometrySet3\FNearest) & ResultOut, [TFunction](API\Runtime\Core\GenericPlatform\TFunction)< bool(const FVector3d &, const FVector3d &)> PointWithinToleranceTest ) const